<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="app">
        <div>{{num | strlen(money)}}</div>
        <button @click="mei">转$</button>
        <button @click="ren">转￥</button>

    </div>
    <script src="./js/vue.js"></script>
    <script>
        var app = new Vue({
            el: "#app",
            data: {
                num: 1234,
                money:""
            },
            filters: {
                strlen: function (value, money) {
                    console.log(value, money);
                    return money + value;
                }
            },
            methods:{
                mei(){
                    this.money = "$";
                },
                ren(){
                    this.money = "￥";
                }
            }
        })
    </script>
</body>

</html>